1. Field of the Invention
The present invention relates to a data managing method that records lyrics associated with recorded audio data in a file separated from audio data management information called RTR_AMG (Real Time Record Audio Management) allocated in a rewritable recording medium, and that searches for a lyric unit written in the separate file prior to reproducing the recorded audio data.
2. Description of the Related Art
A disk-type recording medium such as a Compact Disk (CD) can store high-quality digital audio data permanently, so that it is very popular recording medium in these days.
Recently, a Digital Versatile Disk (called ‘DVD’ hereinafter) has been developed as a new disk-type recording medium. A DVD can store much larger size than a CD, that is, high-quality moving pictures or audio data are recorded in a DVD for much longer time. Therefore, a DVD will be used widely in the near future.
There are three types in a DVD, DVD-ROM for read-only, DVD-R for write-once, and DVD-RAM or DVD-RW for rewritable. For a rewritable DVD, the standardization of data writing format is in progress.
FIG. 1 is a block diagram of an optical disk device that records/reproduces audio data to/from a recording medium.
The disk device configured as FIG. 1 comprises an optical pickup 11 reading signals recorded in a rewritable DVD 10 such as a DVD-RW and writing data streams processed into writable signals onto the rewritable DVD 10; a reproduced signal processor 12 restoring the read signals into compressed digital data; a decoder 13 decoding the compressed digital data to original data; a sampler 18 digitizing an inputted analog signal at a preset sampling rate; an encoder 17 encoding the digitized LPCM data into MPEG-, or AC3-formatted data; a writing processor 16 converting the encoded data from the encoder 17 or LPCM data from the sampler 18 into signals suitable to be written; a controller 14 controlling all elements to conduct user's command such as playback or record; and a memory 15 for storing data temporally.
If an analog signal is applied to the disk device of FIG. 1, the sampler 18 samples the analog signal at the preset sampling rate. Each sampled signal, which is LPCM data, is applied to the encoder 17 that encodes a block of sampled data into compressed data of pre-specified format, for example, MPEG format. The compressed data are then applied to the writing processor 16.
The writing processor 16 converts a series of the compressed data into binary signals which are written in mark/space patterns on the writable DVD 10. Already-compressed digital data from outside are directly processed by the writing processor 16 to be written onto the writable DVD 10.
After recording of audio data, navigation data for them are created and then recorded the writable DVD 10.
FIG. 2 shows the structure of RTR_AMG (Real Time Record Audio ManaGement) recorded as navigation data on a rewritable disk. The RTR_AMG includes RTR_AMGI (RTR Audio Manager General Information), AUDFIT (AUDio File Information Table), ASVFIT (Audio Still Video File Information Table), ORG_PGCI (ORiGinal PGC (ProGram Chain) Information), UD_PGCIT (User Defined PGC Information Table), TXTDT_MG (TeXT DaTa ManaGer), and MNFIT (MaNufacturer's Information Table).
The TXTDT_MG can include lyrics of recorded songs. Therefore, when the controller 14 selects and reproduces a recorded song from the rewritable disk 10, it is able to present lyric text in characters on a screen by reading it from the TXTDT_MG.
Consequently, when a user selects a recorded song to play back from the rewritable DVD 10, he or she is able to view its lyric on a screen.
By the way, the size of RTR_AMG including the TXTDT_MG may be restricted below a certain limit, e.g., 512 KBytes for the purpose of saving resources of a disk player. Furthermore, because an MP3 audio file, which is relatively small in size by lossy coding, is about 2˜4 Mbytes in size, a DVD-RW of about 4.7 GBytes in storage capacity is able to store more than about 1,000 MP3 audio files. Thus, if all lyrics of such many recorded MP3 audio files were written in the TXTDT_MG, the size of RTR_AMG including TXTDT_MG would exceed by far the size limitation.